With the development of network technologies, virtual networks have been widely used. When physical network devices are virtualized to be used in an SDN (Software Defined Network), the SDN includes not only switches, routers, load balancers, firewalls and other network devices that exist in a physical network, but also switches, routers, load balancers, firewalls and other virtual network devices that exist in a distributed virtual network. The boundaries among all virtual network devices often lack visibility and cannot be clearly distinguished. Before making any configuration adjustments on a virtual network, it may be difficult to assess the impact on the virtual network brought by the configuration adjustments. Thus, it is urgent to solve the problems of how to ensure changes on virtual network configurations not to cause undesired effects on the virtual network, and how to quickly recover even when the undesired affects occur.
The disclosed method and system are directed to solve one or more problems set forth above and other problems.